Houmgaor f640cfee27 fix: log SJIS decoding errors instead of silently discarding them
Add SJISToUTF8Lossy() that wraps SJISToUTF8() and logs decode errors at
slog.Debug level. Replace all 31 call sites across 17 files that previously
discarded the error with `_, _ =`. This makes garbled text from malformed
SJIS client data debuggable without adding noise at default log levels.
2026-02-22 17:01:22 +01:00

Erupe

Build and Test CodeQL Go Version Latest Release

Erupe is a community-maintained server emulator for Monster Hunter Frontier written in Go. It is a complete reverse-engineered solution to self-host a Monster Hunter Frontier server, using no code from Capcom.

Quick Start

Pick one of three installation methods, then continue to Quest & Scenario Files.

Docker handles the database automatically. You only need to provide quest files and a config.

  1. Clone the repository and enter the Docker directory:

    git clone https://github.com/Mezeporta/Erupe.git
    cd Erupe
    
  2. Copy and edit the config (set your database password to match docker-compose.yml):

    cp config.example.json docker/config.json
    # Edit docker/config.json — set Database.Host to "db"
    
  3. Download quest/scenario files and extract them to docker/bin/

  4. Start everything:

    cd docker
    docker compose up
    

    pgAdmin is available at http://localhost:5050 for database management.

    See docker/README.md for more details (local builds, troubleshooting).

Option B: Pre-compiled Binary

  1. Download the latest release for your platform from GitHub Releases:

    • erupe-ce for Linux
    • erupe.exe for Windows
  2. Set up PostgreSQL and create a database:

    wget https://github.com/Mezeporta/Erupe/releases/latest/download/SCHEMA.sql
    psql -U postgres -d erupe -f SCHEMA.sql
    
  3. Apply any patch schemas from schemas/patch-schema/ in numerical order:

    psql -U postgres -d erupe -f schemas/patch-schema/01_patch.sql
    # Repeat for each patch file
    
  4. Copy and edit the config:

    cp config.example.json config.json
    # Edit config.json with your database credentials
    
  5. Download quest/scenario files and extract them to bin/

  6. Run: ./erupe-ce

Option C: From Source

Requires Go 1.25+ and PostgreSQL.

  1. Clone and build:

    git clone https://github.com/Mezeporta/Erupe.git
    cd Erupe
    go mod download
    go build -o erupe-ce
    
  2. Set up the database (same as Option B, steps 23)

  3. Copy and edit the config:

    cp config.example.json config.json
    
  4. Download quest/scenario files and extract them to bin/

  5. Run: ./erupe-ce

Quest & Scenario Files

Download: Quest and Scenario Binary Files

These files contain quest definitions and scenario data that the server sends to clients during gameplay. Extract the archive into your bin/ directory (or docker/bin/ for Docker installs). The path must match the BinPath setting in your config (default: "bin").

Without these files, quests will not load and the client will crash.

Client Setup

  1. Obtain a Monster Hunter Frontier client (version G10 or later recommended)
  2. Point the client to your server by editing host.txt or using a launcher to redirect to your server's IP
  3. Launch mhf.exe, select your server, and create an account

If you have an installed copy of Monster Hunter Frontier on an old hard drive, please get in contact so we can archive it!

Updating

From Source

git pull origin main
go mod tidy
go build -o erupe-ce

Check for new patch schemas in schemas/patch-schema/ after pulling — apply any you haven't run yet, in numerical order.

Docker

cd docker
docker compose down
docker compose build
docker compose up

Apply any new patch schemas via pgAdmin or psql into the running container.

Configuration

Edit config.json before starting the server. The essential settings are:

{
  "Host": "127.0.0.1",
  "BinPath": "bin",
  "Language": "en",
  "ClientMode": "ZZ",
  "Database": {
    "Host": "localhost",
    "Port": 5432,
    "User": "postgres",
    "Password": "your_password",
    "Database": "erupe"
  }
}
Setting Description
Host Bind address. Use 127.0.0.1 for local, 0.0.0.0 for remote access
ClientMode Target client version (ZZ, G10, Forward4, etc.)
BinPath Path to quest/scenario files
Language "en" or "jp"

For the full configuration reference (gameplay multipliers, debug options, Discord integration, in-game commands, entrance/channel definitions), see config.example.json and the Erupe Wiki.

Features

  • Multi-version Support: Compatible with all Monster Hunter Frontier versions from Season 6.0 to ZZ
  • Multi-platform: Supports PC, PlayStation 3, PlayStation Vita, and Wii U (up to Z2)
  • Complete Server Emulation: Entry/Sign server, Channel server, and Launcher server
  • Gameplay Customization: Configurable multipliers for experience, currency, and materials
  • Event Systems: Support for Raviente, MezFes, Diva, Festa, and Tournament events
  • Discord Integration: Optional real-time Discord bot integration
  • In-game Commands: Extensible command system with configurable prefixes
  • Developer Tools: Comprehensive logging, packet debugging, and save data dumps

Architecture

Erupe consists of three main server components:

  • Sign Server (Port 53312): Handles authentication and account management
  • Entrance Server (Port 53310): Manages world/server selection
  • Channel Servers (Ports 54001+): Handle game sessions, quests, and player interactions

Multiple channel servers can run simultaneously, organized by world types: Newbie, Normal, Cities, Tavern, Return, and MezFes.

Client Compatibility

Platforms

  • PC
  • PlayStation 3
  • PlayStation Vita
  • Wii U (Up to Z2)

Versions

  • G10-ZZ (ClientMode): Extensively tested with great functionality
  • G3-Z2 (Wii U): Tested with good functionality
  • Forward.4: Basic functionality
  • Season 6.0: Limited functionality (oldest supported version)

Database Schemas

Erupe uses a structured schema system:

  • Initialization Schema: Bootstraps database to version 9.1.0
  • Update Schemas: Production-ready updates for new releases
  • Patch Schemas: Development updates (subject to change)
  • Bundled Schemas: Demo templates for shops, distributions, events, and gacha in schemas/bundled-schema/

Note: Only use patch schemas if you're following active development. They get consolidated into update schemas on release.

Development

Branch Strategy

  • main: Active development branch with the latest features and improvements
  • stable/v9.2.x: Stable release branch for those seeking stability over cutting-edge features

Running Tests

go test -v ./...           # Run all tests
go test -v -race ./...     # Check for race conditions (mandatory before merging)

Troubleshooting

Server won't start

  • Verify PostgreSQL is running: systemctl status postgresql (Linux) or pg_ctl status (Windows)
  • Check database credentials in config.json
  • Ensure all required ports are available and not blocked by firewall

Client can't connect

  • Verify server is listening: netstat -an | grep 53310
  • Check firewall rules allow traffic on ports 53310, 53312, and 54001+
  • Ensure client's host.txt points to correct server IP
  • For remote connections, set "Host" in config.json to 0.0.0.0 or your server's IP

Database schema errors

  • Ensure all patch files are applied in order
  • Check PostgreSQL logs for detailed error messages
  • Verify database user has sufficient privileges

Quest files not loading

  • Confirm BinPath in config.json points to extracted quest/scenario files
  • Verify binary files match your ClientMode setting
  • Check file permissions

Debug Logging

Enable detailed logging in config.json:

{
  "DebugOptions": {
    "LogInboundMessages": true,
    "LogOutboundMessages": true
  }
}

Resources

Changelog

View CHANGELOG.md for version history and changes.

Contributing

See CONTRIBUTING.md for guidelines.

Authors

A list of authors can be found at AUTHORS.md.

Languages
Go 95.4%
PLpgSQL 3.8%
HTML 0.8%